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ANNALS OF THE SOUTH AFRICAN MUSEUM

ANNALE VAN DIE SUID-AFRIKAANSE MUSEUM

Volume 69 Band

December 1975 Desember

Part 4 Deel

CSS

vy M

\ S

Aly ony

Quip NOVI Nas

NOTES ON VARIATION IN PENGUINS AND ON

FOSSIL PENGUINS FROM THE PLIOCENE OF

LANGEBAANWEG, CAPE PROVINCE,

SOUTH AFRICA

GEORGE GAYLORD SIMPSON

Cape Town Kaapstad

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NOTES ON VARIATION IN PENGUINS AND ON FOSSIL PENGUINS

FROM THE PLIOCENE OF LANGEBAANWEG, CAPE PROVINCE,

SOUTH AFRICA

GEORGE GAYLORD SIMPSON

The Simroe Foundation, 5151 East Holmes Street, Tucson, Arizona 85711

(With 5 figures and 4 tables)

[MS. accepted 25 June 1975]

ABSTRACT

Improved statistical data on limb bones of Recent Spheniscus demersus agree with previous

suggestions that adaptively functional elements in penguins have comparatively slight variation.

These data assist in the interpretation of isolated fossil bones. Additional specimens from the

Pliocene of Langebaanweg indicate that Spheniscus predemersus Simpson, 1971, was incorrectly

referred to Spheniscus, and the species is placed in a new genus, Jnguza. A second, larger species

occurs at Langebaanweg, but available material does not warrant further identification or

diagnosis.

CONTENTS

PAGE

mtroductiont, a coe nmr e ioe eo hee tee. tee 9

Comparative data on variation in penguin limb bones . . 60

Eossilssirom)angebaanweger, | eeme aia) eee es eae OS

Acknowledgements ie ee ie Re nee eS Su eel

XA yagenees) SE aie et ae ie Ri N or uch: Gh ich oe nS, 1c: law

INTRODUCTION

These notes consist of two parts. First, a statistical study is made of some

dimensions of limb bones of Spheniscus demersus, not only to increase the data

for variation in penguins generally, but also and particularly to broaden the basis

for sorting and identifying isolated and often incomplete fossil penguin bones.

Next, the considerably enlarged suite of fossil penguin bones from Langebaanweg

is studied. It is reasonably sure that many of these bones, and especially a partial

but characteristic tarsometatarsus, belong to the species previously described as

Spheniscus predemersus (Simpson 1971la). The tarsometatarsus excludes the

species from Spheniscus and indicates reference to a hitherto unnamed and

undefined genus. That genus is technically established later in this paper after

the basis for its distinction and for the reference of predemersus to it has been

established, but to simplify things the new combination Inguza predemersus

will be used throughout.

All fossil specimens here discussed are in the South African Museum.

Reference numbers for all begin SAM-PQ-L, followed by a serial number, but

for brevity they are here given only as L plus the number, which suffices for

identification.

Ann. S. Afr. Mus. 69 (4), 1976: 59-72, 5 figs, 4 tables.

60 ANNALS OF THE SOUTH AFRICAN MUSEUM

All measurements are in millimetres. Other conventions and abbreviations

are explained as needed.

COMPARATIVE DATA ON VARIATION IN PENGUIN LIMB BONES

Many museums now have some osteological material of penguins, but few

have samples of unified origin and large enough to give good estimates of

population variation. The most nearly adequate statistical data are those in

Simpson (1946) for specimens, mostly of Aptenodytes patagonicus, in the

American Museum of Natural History, relatively few specimens, not sexed,

and without precise locality data. Now better data can be given for another

species, Spheniscus demersus, the African black-footed or jackass penguin.

The population represented is that of Robben and Dyer Islands, one north-

west and the other south-east of Cape Town. Although the islands are some

distance apart, their penguin populations are essentially unified as birds banded

on one may turn up on the other. The birds in this sample were caught in an oil-

slick and taken for treatment by the South African National Foundation for the

Conservation of Coastal Birds (SANCCOB) but failed to survive. (Many oiled

birds do recover after treatment.) The dead birds were turned over to the South

African Museum, where their wing and leg bones were macerated. The left limb

bones are in that Museum, and the right limb bones of the same birds were kindly

sent by Dr Q. B. Hendey to the Simroe Foundation for study by the author.

It is conceivable that the sample is biased by the fact that these birds

died from oiling, but that is improbable. There is no apparent reason why

mortality of adult birds from oiling would be correlated with small differences

in the sizes of their limb bones.

Ten of the thirty birds involved are recorded as juvenile, and these were

not included in the statistics even though some of them have apparently fully

ossified limb bones. Three not recorded as juvenile do not have fully adult

ossification and were therefore also excluded. One specimen consisted of wings

only and was excluded because it is desirable to have wing and leg measurements

all on the same individual. One more was disregarded because of poor preser-

vation and one because of pathology (exostoses on some of the bones). Nineteen

specimens were thus measured. Of these, five were recorded as males, one

doubtfully. The doubtful specimen does happen to be smaller than the four

certain males, but it was considered incorrect to exclude it from the sample on

that account. The fourteen females measured are all recorded without question

as to sex.

The dimensions measured were selected primarily for their potential useful-

ness in judging variation and proportions in single bones, especially in fossil

specimens at hand. They are as follows:

Humerus:

a. Maximum longitudinal dimension.

b. Width of shaft about one-third of distance distal to head. In this

Species this is taken at the minimum width of the shaft.

NOTES ON VARIATION IN PENGUINS 61

c. Width of shaft about two-thirds of distance distal to head.

d. From the radial condyle to the longest distal process.

Femur:

a. From the hollow between the head and trochanter to that between

distal condyles.

6. Proximal width.

c. Distal width.

Tibiotarsus:

a. From the proximal articulation (excluding the crest) to the hollow

between distal condyles.

b. Distal width.

Tarsometatarsus:

a. Length on third metatarsal (proximal convexity to distal groove).

b. Width of distal end of third metatarsal.

c. Length on fourth metatarsal (to distal groove).

The following statistics are given in Tables 1, 2 and 4:

N —number of specimens.

OR — observed range in sample.

X —mean and siandard error.

S —Standard deviation and standard error.

VY -—coefficient of variation and standard error.

The males of this living species are in general larger in mean sample esti-

mates than the females, ‘humerus d’ being the only dimension of which this is

not true. However the differences are slight and there is large overlap in all the

observed ranges, still more in the probable population ranges. These bones in

this species cannot be reliably sexed on the basis of size.

The humerus is distinctly more variable in males than in females of this

sample. That could be due to sampling error, but probably is not. Its functional

significance, if any, is not clear. The tarsometatarsus is also somewhat more

variable in males than in females, but here the difference is less and is quite

probably due to sampling error. No sexual difference in variation is indicated

for femur or tibiotarsus.

The coefficients of variation are in general quite small. The mean of the

24 coefficients in Table | is only 3,63. The variation in functionally adaptive

dimensions of birds tends to be low, suggesting that these characters are subject

to effective stabilizing or centripetal selection. It is interesting that this is true

of wing bones in penguins, aqueous fliers, as well as in aerial fliers.

An aid to sorting isolated bones is provided by the ratios of measurements

in associated bones of individuals of one species. Some data from the Spheniscus

demersus sample are given in Table 2. There is no evident sexual distinction in

this respect. These ratios are likely to be different in different species, but they

probably will be close to those for S. demersus in species of approximately the

same size. There is a tendency in Recent species, at least, for the humerus to be

62 ANNALS OF THE SOUTH AFRICAN MUSEUM

TABLE 1

Statistics on Some Limb Bones of Spheniscus demersus

N OR xX N) Vv.

Males

Humerus

a 5 64,0-69,5 67,82 + 1,06 2,37 + 0,75 3,50 + 1,11

b 5 10,0-11,5 10,64 + 0,33 0,74 + 0,24 6,99 + 2,21

c 5 11,7-13,4 12,44 + 0,36 0,80 + 0,25 6,40 + 2,02

d 5 19,9-22,5 21,56 + 0,50 1,12 + 0,35 5,20 + 1,65

Femur

a 5) 65,6-70,0 68,32 + 0,73 1,64 + 0,52 2,40 + 0,76

b 5 14,5-15,5 15,04 + 0,20 0,44 + 0,14 2,96 + 0,94

c 5 13,9-15,0 14,42 + 0,22 0,50 + 0,16 3,45 + 1,09

Tibiotarsus

a 5) 96,7-104,4 101,16 + 1,28 2,87 + 0,91 2,84 + 0,90

b 5 13,1-14,3 13,86 + 0,21 0,46 + 0,15 3,33 + 1,05

Tarsometatarsus

a 5 28,9-32,8 31,26 + 0,66 1,47 + 0,47 4,72 + 1,49

b 5 6,3-7,1 6,76 + 0,15 0,34 + 0,11 5,08 + 1,61

@ 5 26,0-28,5 27,22 + 0,44 0,98 + 0,31 3,61 + 1,14

Females

Humerus

a 14 63,9-69,3 66,66 + 0,51 191 = 0536 2,87 + 0,54

b 14 10,0—10,8 10,43 + 0,07 0,28 -- 0,05 2,64 + 0,50

Cc 14 11,3-12,7 11,94 + 0,09 0,35 + 0,07 ZTE OSS

d 14 20,9-22,9 21,66 + 0,14 0,51 + 0,10 2,34 + 0,44

Femur

a 14 61,9-68,9 65,94 + 0,43 1,61 + 0,30 2,44 + 0,46

b 14 14,1-15,5 14,79 + 0,12 0,44 + 0,08 SO Se OLS)7/

Cc 14 13,6-15,3 14,27 + 0,12 0,45 + 0,09 3,19 + 0,60

Tibiotarsus

a 14 91,8-102,6 97,54 + 0,88 3,29 + 0,62 3,37 + 0,64

b 14 13,1-14,3 13,71 + 0,11 0,42 + 0,08 3,06 + 0,58

Tarsometatarsus

a 14 28,9-32,8 30,79 + 0,28 1,05 + 0,20 3,39 + 0,64

b 14 6,5—-7,4 6,74 + 0,07 0,26 + 0,05 3,93 + 0,74

c 14 25,4-28,0 26,55 + 0,24 0,92 + 0,17 3,45 + 0,65

Symbols are explained in the text.

TABLE 2

Ratios of Some Dimensions in Spheniscus demersus

Humerus a Humerus a Femur a

Femur a Tarsometatarsus a Tarsometatarsus a

N OR N OR x N OR x

WMRIES “5 S$ 6 6 8) USCSRO Mey Sy 25122015 21) 5 2,10—-2,27 | 29

Females 14 0,98-1,04 1,01 14 2,09-2,28 2,17 14 2,08-2,27 2,14

Symbols are explained in the text.

longer relative to the femur and tarsometatarsus the larger the species (Simpson

1946: table 8).

Since limb bones cannot be sexed by size in S. demersus and this is

apparently usually but not necessarily always true in penguins, statistics were

also calculated for some dimensions in a sample of S. demersus with the most

NOTES ON VARIATION IN PENGUINS 63

probable ratio of males to females, that is, equal numbers of the two sexes.

This includes the five males available and five females taken at random (using

a table of random numbers applied to the serial numbers of these specimens).

The dimensions were selected for comparison with available specimens of fossil

humeri and femora from Langebaanweg. Results are given in Table 4.

FOSSILS FROM LANGEBAANWEG

Penguins from the Pliocene of Langebaanweg were previously described by

the author (Simpson 1971a) on the basis of three humeri, one essentially com-

plete and two fragmentary, a partial tibiotarsus, two complete femora, and one

pedal phalanx. The humeri were referred to a then new species as Spheniscus

predemersus (Fig. 1). It will be shown below that the generic ascription was

almost certainly erroneous, and the name /nguza predemersus will be used here.

Later discoveries have added greatly to the available materials, although

even now they are not wholly adequate. Most of the bones of the wings and legs

are represented, although some, unfortunately including the tarsometatarsus,

only by imperfect specimens. The provenience is described in Hendey (1974)

and Dr Hendey has added information in personal communication. The speci-

mens are from the ‘E’ Quarry at Langebaanweg, and for the most part from the

area designated as ‘East Stream’ (Hendey 1974: fig. 3). All are from the Vars-

water Formation, and with one exception they are from “Bed 2’ of Hendey (1974:

table 4), which he is now proposing to call the ‘Quartzose Sand Member’. That

member is comprised of deposits accumulated in and adjacent to an estuary

and its fauna is made up largely of terrestrial vertebrates. Besides the penguins,

aquatic or amphibious elements are represented by an otter, Enhydriodon

africanus, and a seal, Prionodelphis capensis. These are at present the only fossil

penguins found in a predominantly non-marine association. The one exception

referred to above is from the Gravel Member (=Bed 1), the basal unit of the

Varswater Formation in which marine fossils are predominant.

This deposit is the type of the proposed South African provincial land

mammal stage and age Langebaanian, Pliocene in age and tentatively correlated

with the Astian of Europe and the Rexroadian of North America (Hendey 1974:

table 8).

Renewed study of the systematics of these fossil penguins with enlarged

samples is based on the humeri, femora, tibiotarsi, and tarsometatarsi. The

other bones, although numerous, are less characteristic and do not add to con-

clusions based on these bones.

Measurements are given in Table 3. The dimensions are the same as those

specified in the text above and used in Tables 1 and 2. Statistics derived from

these measurements are given in Table 4 and there compared with statistics

for a sample of Recent Spheniscus demersus made to include equal numbers of

the two sexes, as noted in previous text. These dimensions, and therefore the

measurements, differ somewhat from those previously used for the smaller

sample (Simpson 197la: table 1). For ‘humerus b’ and ‘humerus c’ the co-

64 ANNALS OF THE SOUTH AFRICAN MUSEUM

ILLIA LLV UU LLL LLL LIL LLL

a4 113 114 15 116 117

Fig.1. Inguza predemersus, type, humerus SAM-—PQ-L6510. Ventral, dorsal and postaxial

views. Scale in mm.

NOTES ON VARIATION IN PENGUINS

TABLE 3

Measurements of some Limb Bones of Fossil Penguins from Langebaanweg

Specimen No. Dimension

Humerus

a b Cc d

L6510, holotype of

Inguza predemersus 59,0 8,6 10,0 17,8

L123010 7-5 9,6 10,9 18,9

L14853 . — 8,7 1 18,4

L12887A — 9,4 Wee 19,3

122952) — 10,0 IEA =

121928 . — 9,8 = =

Femur

a b Cc

L23002 . 59,8 — 13,3

122983 . 61,5 — 13,4

ILPRAAUT/ See on cer, tao Wen 62,3 13,9 13,9

L122954 SO Riek Bsc ae — 14,4 —

L12524A — — 14,5

13154 . dsl 18,1 16,3

13656" *. S — 17,6

L13066A — 18,7 —

Tibiotarsus

a b

L23012 . 85,2 IES)

122950 . ca. 92 123}

Tarsometatarsus

a b Cc

L23018 . DTD S63 24,2

L22974 . — 4,7 —

122985 . — ca. 74 —

Symbols are explained in the text.

TABLE 4

Some Statistical Data on a Sample with Equal Numbers of Males and Females of Spheniscus

demersus and on Available Fossils from Langebaanweg

Sample Dimension N OR x

Spheniscus Humerusb 10 = 10,0-11,5 10,59 + 0,16

demersus Humerus c 10 = 11,7-13,4 12,24 + 0,16

Humerusd 10 = 19,9-22,5 21,63 + 0,25

Femur a 10 61,9-70,0 66,63 + 0,79

Femur c 10 13,6-15,0 14,19 + 0,14

Inguza

predemersus Humerus 6 6 8,6-10,0 9,35 + 0,24

Humerus c 5 10,0-11,7 10,98 + 0,28

Humerus d 4 17,8-19,3 18,60 + 0,32

Femur a 3 59,8-62,3 61,20 + 0,74

Femur c 4 13,3-14,5 13,78 + 0,28

Mixed sample, all measureable bones from Langebaanweg

Femur a 5 59,8-79,5 67,64 + 4,02

Femur c 6 13,3-17,6 14,83 + 0,71

Symbols are explained in the text.

O55 =e 0519.

9,00 + 2,01

1,74 + 0,50

4,87 + 1,09

4,21 + 0,94

3472210383

3,76 + 0,84

3,12 + 0,70

Gul

66 ANNALS OF THE SOUTH AFRICAN MUSEUM

efficients of variation are somewhat higher than for S. demersus or, so far as

data are available, most other Recent penguins. However the difference is not

great enough to indicate that it is probably not due either to sampling error or

to somewhat greater real variability within a single species. For ‘humerus da’,

generally a less variable dimension, V is not statistically different from that of

S. demersus. Except for the moderate variation in these dimensions and in the

ratios among them, these humeri do not differ appreciably in morphology.

They are therefore all tentatively referred to Inguza predemersus, the more

common but, as will now appear, not the only species of penguins in this fauna.

There are seven tibiotarsi in the collection but only one is complete, and

although three others are nearly so only one other gives approximate comparable

measurements. The variation in size is considerable, but again not enough to

indicate reliably that more than one species is represented. The two most

complete specimens, L23012 and L22950, are within a size range appropriate

for association with humeri referred to Inguza predemersus.

The situation regarding the femora is quite different. For the six femora

affording one or more useful measurements the coefficients of variation for all

taken together are decidedly too high to be derived from a single species of

penguins. It is also evident in Table 3 that they fall into two quite distinct size

groups. The smaller group, L23002, L22983, L22117, L22954 and L12524A, is

of appropriate size for association with the humeri referred to /nguza pre-

demersus (Fig. 2). The ratio of the mean for ‘humerus a’ (two specimens) to the

mean for ‘femur a’ (three specimens) is 0,95. In Spheniscus demersus it is 0,99

(Table 2), not significantly different. The femora L13154 and L3656 give a

corresponding ratio of 0,75, which is significantly different, and these femora

surely belong to a second, larger species, to which L13066 also belongs (Fig. 3).

‘Femur a’ for specimens referred to Jnguza predemersus has unusually

slight variation and ‘femur c’ unusually large variation. However N is small

for both (3 and 4, respectively), standard errors are correspondingly large, and

the differences of values of V frorn those found in Spheniscus demersus are not

significant.

The specimen mentioned above as having come from the Gravel Member

is L21628, the distal part of a femur. The end is too abraded or corroded for

useful measurement, but this bone agrees closely with the larger specimens from

the Quartzose Sand Member. Dr Hendey (pers. com.) notes that ‘The Gravel

Member does include derived fossils, probably of Miocene Age’. It is, however,

probable that this fragment represents the same species as the larger one in the

overlying member.

There are 16 partial tarsometatarsi in the collection, but most of these

are scraps, especially distal condyles, from which little can be learned. The most

extensive, L23018 (Fig. 4), includes the third and fourth tarsometatarsals and

the dorsal, but not the plantar, part of the proximal end. The ratio for mean

‘humerus a@ of two Inguza predemersus to ‘tarsometatarsus a’ of this specimen

is 2,14, which suggests that these animals were of quite closely the same size

NOTES ON VARIATION IN PENGUINS 6

—

114

ALIA IAIN

]

III

Fig. 2. Inguza predemersus, femur SAM—-PQ-L22117. Anterior and posterior views.

and very likely of the same species. L23401, a fourth tarsometatarsal with some

adjacent bone, and L22974, most of a third tarsometatarsal with some adjacent

bone, also may be referred to this species, to which most of the lesser fragments

probably belong. There are, however, some scraps, notably L22985, the distal

part of the third tarsometatarsal and some adjacent bone, and L23402, approxi-

mately the same but even more poorly preserved, which belong to a definitely

distinct and larger species (Fig. 5). The species could well be the same as that

represented by the larger femora.

On L23018 it can be determined that the medial intermetatarsal foramen

(or inner proximal foramen of Zusi 1975) is larger than the lateral foramen and

slightly more distal. It opens on the plantar side distal to the medial (inner)

68 ANNALS OF THE SOUTH AFRICAN MUSEUM

Fig. 3. Spheniscidae indet. (left) and Inguza predemersus (right), femora SAM-PQ-L13154

and SAM-PQ-L22117. Anterior views.

Borne (6 9

ter nemeancarnene Somme

———ee

ee Cem

SE « ©)

ee get

s pemenmenmnnel Ww

7—_—_—— ot

—— =§ «)

—mmm gue

————- S§« sO)

NOTES ON VARIATION IN PENGUINS 69

= 6 I 8

1 1 7 I

Fig. 4. Inguza predemersus, tarsometatarsus SAM—PQ-L23018. Dorsal and plantar views.

calcaneal ridge. These characters definitely exclude reference to the genus

Spheniscus in which the medial foramen is relatively smaller, is somewhat more

proximal, and opens on the medial side of the medial calcaneal ridge. (See

Zusi 1975, who shows that the latter arrangement occurs in Eudyptes; I have

confirmed that it also occurs and is apparently invariable in Spheniscus

demersus.) Among Recent penguins the genera Aptenodytes and Pygoscelis have

the arrangement of intermetatarsal foramina more as in this fossil. The Recent

species of those genera are decidedly larger than the fossil, even in Pygoscelts.

The tarsometatarsus is also less elongate, the foramina relatively less proximal,

70 ANNALS OF THE SOUTH AFRICAN MUSEUM

Fig. 5. Spheniscidae indet. (left) and Inguza predemersus (right), tarsometatarsi

SAM-PQ-L22985 and SAM—PQ-L23018. Dorsal views.

more nearly in a transverse line, and more nearly equal in size. Reference of

the fossil to Pygoscelis or Aptenodytes is not tenable.

It seems open to little question that the holotype humerus of /nguza prede-

mersus, originally referred to Spheniscus, and the tarsometatarsus, now available

and added to the hypodigm, belong to the same species and that the species

neither belongs in nor was ancestral to Spheniscus. The humerus really differs

little from that of Spheniscus demersus. Apart from smaller size, it has the

shaft slightly more sigmoid and it lacks a preaxial angle or tubercle; it now

follows that these slight differences are associated with a tarsometatarsus surely

generically distinct from Spheniscus. They therefore now appear to be generic

characters although that would hardly be tenable on the basis of the humeri

alone. The author has been unable to find a previously named extinct genus to

which this species can be reasonably referred. Duntroonornis from the early

Oligocene of New Zealand may come as close as any, but its less elongate

tarsometatarsus, smaller and more unequal foramina, and perhaps the obliquity

of the metatarsals, if that is not caused by crushing of the only known specimen,

distinguish it (see Simpson 19716). ‘Spheniscus’ predemersus must therefore be

referred to a new, extinct genus which will now be formally proposed. It is

improbable that this genus is ancestral or close to any living penguins, but it

NOTES ON VARIATION IN PENGUINS 71

may conjecturally have some special relationship with Pygoscelis or perhaps

even Aptenodytes.

It is probably impossible and certainly inadvisable to identify or name

the second, larger species from Langebaanweg on the basis of specimens now

in hand. It is certainly distinct from Inguza predemersus, but the available

specimens are otherwise not diagnostic.

Technical validation of the new generic name and revision of the specific

name follow.

Order SPHENISCIFORMES

Family Spheniscidae

Inguza, gen. n.

Etymology: ‘Inguza’ is given by McLachlan & Liversidge (1970) as a ‘native

[South African] name’ for penguins. Greek derivatives appropriate for penguins

have become rather overdone and repetitious. Native African languages do not

have gender in the Latin sense, so this name is arbitrarily designated as

masculine.

Type-species: Spheniscus predemersus Simpson, 1971.

Included species: Type only.

Known distribution: Langebaanian, Pliocene, in the Quartzose Sand Member

of the Varswater Formation at Langebaanweg, Cape Province, Republic of

South Africa.

Diagnosis: Humerus with shaft narrower proximally, somewhat sigmoid;

tricipital fossa strongly bipartite; preaxial angulation absent. Tarsometatarsus

elongate; intermetatarsal foramina proximal; medial foramen larger than lateral

foramen, slightly more distal, opening distal to the medial calcaneal ridge on

the plantar surface; third and fourth metatarsals straight.

Inguza predemersus (Simpson, 1971)

Spheniscus predemersus Simpson, 1971a: 1144.

Etymology: Pre+- demersus, as older than known Spheniscus demersus and

erroneously believed to be specially related to the latter.

Holotype: SAM-PQ-L6510, left humerus, essentially complete.

Present Hypodigm: The type and the following:

L23010, complete humerus, L14853, L12887A, 122952, and L21928,

partial humeri.

L22117A, complete femur, L23002, L22983, L122954, and L12524A,

partial femora.

L23012, complete, and L22930, nearly complete, tibiotarsi.

L23018 and L22974, partial tarsometatarsi.

2 ANNALS OF THE SOUTH AFRICAN MUSEUM

Numerous other bones, mostly fragmentary, almost certainly belong to

this species but have not yet entered explicitly into the present concepts

and diagnoses of the genus and species.

Known distribution: As for the genus.

Diagnosis: Only known species of Jnguza. Measurements in Table 3.

ACKNOWLEDGEMENTS

I am greatly indebted to the South African Museum and to Dr Q. B. Hendey

who provided the material for the study of variation in Spheniscus demersus,

arranged the loan of the fossil specimens, gave some further information, and

reviewed the manuscript of this paper. The study has been performed at the

Simroe Foundation under the joint support from that foundation and the

Department of Geosciences of the University of Arizona, Tucson, U.S.A.

The illustrations are by Mr S. Kannemeyer of the South African Museum.

REFERENCES

HENDEY, Q. B. 1974. The late Cenozoic Carnivora of the south-western Cape Province. — Aun.

S. Afr. Mus. 63: 1-369.

McLACHLAN, G. R. & LiversipGE, R., revisers. 1970. Roberts birds of South Africa. Cape

Town: Central News Agency.

Simpson, G. G. 1946. Fossil penguins.— Bull. Amer. Mus. nat. Hist. 87: 1-99.

Simpson, G. G. 1971a. Fossil penguin from the late Cenozoic of South Africa.— Science 171:

1144-1145.

SIMPSON, G. G. 19716. A review of the pre-Pliocene penguins of New Zealand.— Bull. Amer.

Mus. nat. Hist. 144: 319-378.

Zust, R. L. 1975. An interpretation of skull structure in penguins.* Jn: STONEHOUSE, B., ed.

The biology of penguins: 59-84. London and Basingstoke: Macmillan.

*This study also refers to bones other than the skull.

6. SYSTEMATIC papers must conform with the International code of zoological nomenclature

(particularly Articles 22 and 51).

Names of new taxa, combinations, synonyms, etc., when used for the first time, must be

followed by the appropriate Latin (not English) abbreviation, e.g. gen. n., sp. n., comb. n.,

syn. n., etc.

An author’s name when cited must follow the name of the taxon without intervening

punctuation and not be abbreviated; if the year is added, a comma must separate author’s

name and year. The author’s name (and date, if cited) must be placed in parentheses if a

species or subspecies is transferred from its original genus. The name of a subsequent user of

a scientific name must be separated from the scientific name by a colon.

Synonymy arrangement should be according to chronology of names, i.e. all published

scientific names by which the species previously has been designated are listed in chronological

order, with all references to that name following in chronological order, e.g.:

Family Nuculanidae

Nuculana (Lembulus) bicuspidata (Gould, 1845)

Figs 14-15A

Nucula (Leda) bicuspidata Gould, 1845: 37.

Leda plicifera A. Adams, 1856: 50.

Laeda bicuspidata Hanley, 1859: 118, pl. 228 (fig. 73). Sowerby, 1871: pl. 2 (figs 8a—b).

Nucula largillierti Philippi, 1861: 87

Leda bicuspidata: Nicklés, 1950: 163, fig. 301; 1955: 110. Barnard, 1964: 234, figs 8-9.

Note punctuation in the above example:

comma separates author’s name and year

semicolon separates more than one reference by the same author

full stop separates references by different authors

figures of plates are enclosed in parentheses to distinguish them from text-figures

dash, not comma, separates consecutive numbers

Synonymy arrangement according to chronology of bibliographic references, whereby

the year is placed in front of each entry, and the synonym repeated in full for each entry, is

not acceptable.

In describing new species, one specimen must be designated as the holotype; other speci-

mens mentioned in the original description are to be designated paratypes; additional material

not regarded as paratypes should be listed separately. The complete data (registration number,

depository, description of specimen, locality, collector, date) of the holotype and paratypes

must be recorded, e.g.:

Holotype

SAM-A13535 in the South African Museum, Cape Town. Adult female from mid-tide region, King’s Beach,

Port Elizabeth (33.51S, 25.39E), collected by A. Smith, 15 January 1973.

Note standard form of writing South African Museum registration numbers and of date.

7. SPECIAL HOUSE RULES

Capital initial letters

(a) The Figures, Maps and Tables of the paper when referred to in the text

e.g. *... the Figure depicting C. namacolus...’

“,..1in C. namacolus (Fig. 10)...’

(b) The prefixes of prefixed surnames in all languages, when used in the text, if not preceded

by initials or full names

e.g. Du Toit but A. L. du Toit

Von Huene but F. von Huene

e.g. Therocephalia, but therocephalian

Punctuation should be loose, omitting all not strictly necessary

Reference to the author should be expressed in the third person

Roman numerals should be converted to arabic, except when forming part of the title of a

book or article, such as

‘Revision of the Crustacea. Part VIII. The Amphipoda.’

Specific name must not stand alone, but be preceded by the generic name or its abbreviation

to initial capital letter, provided the same generic name is used consecutively.